<?php
class SubPages {
	
	private $each_disNums; //每页显示的条目数
	private $nums; //总条目数
	private $current_page; //当前被选中的页
	private $sub_pages; //每次显示的页数
	private $pageNums; //总页数
	private $page_array = array (); //用来构造分页的数组
	private $subPage_link; //每个分页的链接
	private $subPage_type; //显示分页的类型
	/*
   __construct是SubPages的构造函数，用来在创建类的时候自动运行.
   @$each_disNums   每页显示的条目数
   @nums     总条目数
   @current_num     当前被选中的页
   @sub_pages       每次显示的页数
   @subPage_link    每个分页的链接
   @subPage_type    显示分页的类型
  
   当@subPage_type=1的时候为普通分页模式
         example：   共4523条记录,每页显示10条,当前第1/453页 [首页] [上页] [下页] [尾页]
         当@subPage_type=2的时候为经典分页样式
         example：   当前第1/453页 [首页] [上页] 1 2 3 4 5 6 7 8 9 10 [下页] [尾页]
   */
	function __construct($each_disNums, $nums, $current_page, $sub_pages, $subPage_link, $subPage_type) {
		if ($each_disNums && $nums && $current_page && $sub_pages && $subPage_link && $subPage_type) {
			$this->each_disNums = intval ( $each_disNums );
			$this->nums = intval ( $nums );
			if (! $current_page) {
				$this->current_page = 1;
			} else {
				$this->current_page = intval ( $current_page );
			}
			$this->sub_pages = intval ( $sub_pages );
			$this->pageNums = ceil ( $nums / $each_disNums );
			$this->subPage_link = $subPage_link;
			$this->show_SubPages ( $subPage_type );
		
		//echo $this->pageNums."--".$this->sub_pages;
		}
	
	}
	
	/*
    __destruct析构函数，当类不在使用的时候调用，该函数用来释放资源。
   */
	function __destruct() {
		unset ( $each_disNums );
		unset ( $nums );
		unset ( $current_page );
		unset ( $sub_pages );
		unset ( $pageNums );
		unset ( $page_array );
		unset ( $subPage_link );
		unset ( $subPage_type );
	}
	
	/*
    show_SubPages函数用在构造函数里面。而且用来判断显示什么样子的分页  
   */
	function show_SubPages($subPage_type) {
		if ($subPage_type == 1) {
			$this->subPageCss1 ();
		} elseif ($subPage_type == 2) {
			$this->subPageCss2 ();
		}
	}
	
	/*
    用来给建立分页的数组初始化的函数。
   */
	function initArray() {
		for($i = 0; $i < $this->sub_pages; $i ++) {
			$this->page_array [$i] = $i;
		}
		return $this->page_array;
	}
	
	/*
    construct_num_Page该函数使用来构造显示的条目
    即使：[1][2][3][4][5][6][7][8][9][10]
   */
	function construct_num_Page() {
		if ($this->pageNums < $this->sub_pages) {
			$current_array = array ();
			for($i = 0; $i < $this->pageNums; $i ++) {
				$current_array [$i] = $i + 1;
			}
		} else {
			$current_array = $this->initArray ();
			if ($this->current_page <= 3) {
				for($i = 0; $i < count ( $current_array ); $i ++) {
					$current_array [$i] = $i + 1;
				}
			} elseif ($this->current_page <= $this->pageNums && $this->current_page > $this->pageNums - $this->sub_pages + 1) {
				for($i = 0; $i < count ( $current_array ); $i ++) {
					$current_array [$i] = ($this->pageNums) - ($this->sub_pages) + 1 + $i;
				}
			} else {
				for($i = 0; $i < count ( $current_array ); $i ++) {
					$current_array [$i] = $this->current_page - 2 + $i;
				}
			}
		}
		
		return $current_array;
	}
	
	/*
   构造普通模式的分页
   共4523条记录,每页显示10条,当前第1/453页 [首页] [上页] [下页] [尾页]
   */
	function subPageCss1() {
		$subPageCss1Str = "";
		$subPageCss1Str .= "共" . $this->nums . "条记录，";
		$subPageCss1Str .= "每页显示" . $this->each_disNums . "条，";
		$subPageCss1Str .= "当前第" . $this->current_page . "/" . $this->pageNums . "页 ";
		if ($this->current_page > 1) {
			$firstPageUrl = $this->subPage_link . "1";
			$prewPageUrl = $this->subPage_link . ($this->current_page - 1);
			$subPageCss1Str .= "<a href='$firstPageUrl'>首页</a>";
			$subPageCss1Str .= "<a href='$prewPageUrl'>上一页</a>";
		} else {
			$subPageCss1Str .= "首页";
			$subPageCss1Str .= "上一页";
		}
		
		if ($this->current_page < $this->pageNums) {
			$lastPageUrl = $this->subPage_link . $this->pageNums;
			$nextPageUrl = $this->subPage_link . ($this->current_page + 1);
			$subPageCss1Str .= " <a href='$nextPageUrl'>下一页</a>";
			$subPageCss1Str .= "<a href='$lastPageUrl'>尾页</a>";
		} else {
			$subPageCss1Str .= "下一页";
			$subPageCss1Str .= "尾页";
		}
		
		echo $subPageCss1Str;
	
	}
	
	/*
   构造经典模式的分页
   当前第1/453页 [首页] [上页] 1 2 3 4 5 6 7 8 9 10 [下页] [尾页]
   */
	function subPageCss2() {
		$subPageCss2Str = "";
		$subPageCss2Str .= "当前第" . $this->current_page . "/" . $this->pageNums . "页 ";
		
		if ($this->current_page > 1) {
			$firstPageUrl = $this->subPage_link . "1";
			$prewPageUrl = $this->subPage_link . ($this->current_page - 1);
			$subPageCss2Str .= "<a href='$firstPageUrl'>首页</a>";
			$subPageCss2Str .= "<a href='$prewPageUrl'>上一页</a>";
		} else {
			$subPageCss2Str .= "首页";
			$subPageCss2Str .= "上一页";
		}
		
		$a = $this->construct_num_Page ();
		for($i = 0; $i < count ( $a ); $i ++) {
			$s = $a [$i];
			if ($s == $this->current_page) {
				$subPageCss2Str .= "<span style='color:red;font-weight:bold;'>" . $s . "</span>";
			} else {
				$url = $this->subPage_link . $s;
				$subPageCss2Str .= "<a href='$url'>" . $s . "</a>";
			}
		}
		
		if ($this->current_page < $this->pageNums) {
			$lastPageUrl = $this->subPage_link . $this->pageNums;
			$nextPageUrl = $this->subPage_link . ($this->current_page + 1);
			$subPageCss2Str .= " <a href='$nextPageUrl'>下一页</a>";
			$subPageCss2Str .= "<a href='$lastPageUrl'>尾页</a>";
		} else {
			$subPageCss2Str .= "下一页";
			$subPageCss2Str .= "尾页";
		}
		echo $subPageCss2Str;
	}

}

?>